In the Earth’s 4.6 billion year history, over 99% of all the species that have ever existed have become extinct. In the majority of cases, these extinctions are due to competition between species for space, food, or other resources; or that a species did not adapt sufficiently or quickly enough to changes in the environment. Extinction is a natural and on-going part of the biosphere’s engineering that continues at a background rate. This constant cycle of extinction, adaptation, and evolution means that as one species meets its demise, another will take its ecological niche. Over long time periods (thousands or millions of years), this can...